A new type of coaxial counter-rotating turbine drill tool

Abstract

The application belongs to the technical field of petroleum drilling equipment, and particularly relates to a novel coaxial counter-rotating turbine drilling tool of a jet flow motor, which comprises an upper joint, a turbine sleeve, an upper bearing, a central turbine shaft, a pressing nut, a turbine group, a height increasing ring, a connecting sleeve, an intermediate bearing, a gear outer sleeve, a week gear train, a lower bearing, a lower joint, an underreaming bit connecting shaft, an underreaming bit and a pilot bit. The turbine group is composed of a turbine stator and a turbine rotor. The week gear train comprises an input gear, a gear frame, a fastening nut, an intermediate gear, a sliding shaft sleeve, a positioning nut and an output gear. The upper joint, the turbine sleeve, the connecting sleeve, the gear outer sleeve and the lower joint are sequentially threadedly connected. The pilot bit is threadedly connected with the central turbine shaft, and the underreaming bit is threadedly connected with the underreaming bit connecting shaft. The turbine stator is installed on the turbine sleeve through interference fit, and the turbine rotor and the height increasing ring are sleeved on the central turbine shaft. The drilling tool improves drilling efficiency and reduces production cost.

Description

Technical Field

[0001] This invention belongs to the field of oil drilling equipment technology, specifically relating to a novel coaxial counter-rotating turbine drill bit with a jet motor. Background Technology

[0002] Currently, in oil and gas well drilling, turbine drill bits have become one of the main tools for downhole power drilling due to their advantages such as high rotational speed, long stator and rotor service life, and high pressure resistance. Downhole turbine drill bits use a rotating drill bit to impact, compress, scrape, and grind the outer rock, thereby achieving rock breaking. Because the rock breaking strength is related to the surrounding rock stress in the formation, smaller reaming bits can be used for drilling. After drilling a small hole in the formation, the surrounding rock stress around the hole wall can be released and cracks can be formed. When using reaming bits for further drilling, the drilling difficulty is reduced, drillability is greatly improved, and thus the drilling speed is increased.

[0003] However, existing turbine drill bits, due to their high rotational speed, result in relatively low drill torque, thus reducing overall drilling efficiency and limiting their application. Some turbine drill bits with reducers are difficult to apply effectively due to their cumbersome structure and complex downhole environment. Furthermore, existing reaming drilling processes involve long and inefficient two-pass drilling, while reaming while drilling also presents various dangers and limitations due to the excessive distance between the lead drill bit and the reamer, and the need for both to rotate concentrically at the same speed. Therefore, improvements are necessary to address these issues. Summary of the Invention

[0004] To address the problems existing in the background art, the present invention provides a novel coaxial counter-rotating turbine drill bit with jet motor, which improves drilling efficiency and reduces production costs.

[0005] The technical solution adopted in this invention is as follows: a novel coaxial counter-rotating turbine drill bit for jet motors, comprising an upper connector, a turbine sleeve, an upper bearing, a central turbine shaft, a clamping nut, a turbine assembly, a heightening ring, a connecting sleeve, an intermediate bearing, a gear sleeve, a planetary gear train, a lower bearing, a lower connector, a reaming drill bit connecting shaft, a reaming drill bit, and a leading drill bit; the turbine assembly consists of a turbine stator and a turbine rotor, with circumferentially distributed axial-flow tangential square holes below the jet end face of the turbine rotor, and circumferentially distributed pressure fins on the end face of the main body of the axial-flow tangential square holes; the planetary gear train comprises an input gear, a gear carrier, a fastening nut, an intermediate gear, a sliding bushing, a positioning nut, and an output gear; The upper connector, turbine sleeve, connecting sleeve, gear sleeve, and lower connector are sequentially threaded together; the leading drill bit is threaded to the central turbine shaft, and the reaming drill bit is threaded to the reaming drill bit connecting shaft; the turbine stator is mounted on the turbine sleeve with an interference fit, and the turbine rotor and heightening ring are fitted on the central turbine shaft and fixed to the central turbine shaft by a clamping nut threaded to the central turbine shaft; the input gear and output gear are respectively mounted on the central turbine shaft and the reaming drill bit connecting shaft by fastening nuts, the gear carrier is mounted on the central turbine shaft, the sliding bushing is nested on the gear carrier, the intermediate gear is nested on the sliding bushing, and the sliding bushing and intermediate gear are axially fixed by a positioning nut.

[0006] Furthermore, the central turbine shaft is supported for rotation by an upper bearing and an intermediate bearing.

[0007] Furthermore, the reamer connecting shaft is supported for rotation by a lower bearing.

[0008] Furthermore, the input gear and the output gear are circumferentially fixed by a key.

[0009] Furthermore, the torque of the central turbine shaft is adjusted by adjusting the relationship between the number of turbine rotors and heightening rings.

[0010] Furthermore, the lead drill bit and the reamer are spaced a specific distance apart in the axial direction.

[0011] Furthermore, the bearing assembly, consisting of an upper bearing, an intermediate bearing, and a lower bearing, is used to support the rotation of the shaft system.

[0012] Furthermore, when drilling fluid enters the turbine rotor, the turbine blades accelerate to form a tangential jet that drives the turbine to rotate, while the turbine rotor is axially forced and flows out from the axial orifice of the turbine. The axial flow forced pressure can effectively assist the turbine to rotate and generate torque, thereby rotating the central turbine shaft to the bottom hole drill bit for drilling.

[0013] Furthermore, the turbine stator and rotor are arranged alternately. After the high-pressure drilling fluid flows out, it quickly flows into the next stage until it flows out of the turbine assembly. During this process, the fluid energy of the drilling fluid is converted into mechanical energy, which drives the drill bit to rotate. Due to the structure of its turbine stator, the fluid energy of the drilling fluid is converted into tangential force, which simultaneously forms axial flow pressure and drives the turbine to rotate. Therefore, it can improve the energy utilization rate and effectively increase torque and reduce speed.

[0014] Furthermore, the reversing gear set, consisting of the planetary gear train and the gear sleeve, is fitted onto the central turbine shaft after the reamer bit connecting shaft is connected to the reamer bit. The reamer bit connecting shaft and the central turbine shaft are connected through the planetary gear train, thereby enabling the counter-rotation of the reamer bit and the leading reamer bit through the planetary gear train.

[0015] Furthermore, the input gear of the planetary gear system is mounted on the central turbine shaft, the output gear is mounted on the reamer bit connecting shaft, and the intermediate gear is mounted on the central turbine shaft via a gear carrier. The gears mesh with each other and have a specific ratio, thereby enabling the reamer bit and the lead-in bit to control the rotational speed and torque of the drill bit during drilling at a certain ratio.

[0016] Furthermore, the number of turbine rotor stages can be increased or decreased as needed, thereby adjusting the torque and speed of the lead drill bit. The number of turbine stators remains unchanged to facilitate positioning. The turbine stators and turbine rotor do not directly contact each other to avoid friction that could affect the performance of the drill bit.

[0017] Furthermore, when the drilling fluid enters, it can simultaneously form a tangential jet and axial flow pressure, thereby generating greater torque and achieving better rock-breaking effect. During operation, the number of turbine rotors can be adjusted according to different working conditions to ensure that the tool drilling rate can be effectively improved under various circumstances.

[0018] The beneficial effects of this invention are: it provides a novel coaxial counter-rotating turbine drill string with a jet motor, improving drilling efficiency and reducing production costs. Compared with existing technologies: (1) The special structure of the turbine rotor enables the turbine rotor to achieve both tangential jet and axial flow pressure functions at the same time, which improves energy utilization, effectively reduces the rotational speed while increasing the drill bit torque, thereby improving drilling efficiency. (2) Simultaneous installation of lead drill bit and reamer drill bit for drilling simplifies the drilling process, reduces the occurrence of downhole accidents, and effectively improves rock breaking efficiency and drilling speed. (3) By using the rotating gear system to make the leading drill bit and the reaming drill bit rotate in opposite directions, the gear ratio can also be adjusted to change the speed relationship between the leading drill bit and the reaming drill bit, so as to realize the free ratio of the speed between the leading drill bit and the reaming drill bit, which can better cope with complex working conditions under different geological conditions. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the structure of the novel coaxial counter-rotating turbine drill bit with jet motor in Embodiment 1; Figure 2 yes Figure 1 A magnified view of part A in the image; Figure 3 yes Figure 1A magnified view of part B in the image; Figure 4 yes Figure 1 A magnified view of part C; Figure 5 This is a schematic diagram of the planetary gear system in Example 1; Figure 6 This is a partial cross-sectional view of the turbine rotor in Embodiment 1; Figure 7 This is a three-dimensional structural diagram of the turbine rotor in Embodiment 1. Detailed Implementation

[0020] Example

[0021] Referring to the figures, a novel coaxial counter-rotating turbine drill bit with a jet motor is described. The novel coaxial counter-rotating turbine drill bit with a jet motor includes an upper connector 1, a turbine sleeve 2, an upper bearing 3, a central turbine shaft 4, a clamping nut 5, a turbine assembly 6, a heightening ring 7, a connecting sleeve 8, an intermediate bearing 9, a gear sleeve 10, a planetary gear train 11, a lower bearing 12, a lower connector 13, a reaming bit connecting shaft 14, a reaming bit 15, and a leading-hole bit 16; the turbine assembly consists of… The turbine stator 601 and turbine rotor 602 are composed of a turbine stator 601 and a turbine rotor 602. The turbine rotor has circumferentially distributed axial flow tangential square holes 6021 below the jet end face. The end face of the main body of the axial flow tangential square holes is provided with circumferentially distributed pressure fins 6022. The planetary gear system includes an input gear 1101, a gear frame 1102, a fastening nut 1103, an intermediate gear 1104, a sliding bushing 1105, a positioning nut 1106, and an output gear 1107. The upper connector, turbine sleeve, connecting sleeve, gear sleeve, and lower connector are sequentially threaded together; the leading drill bit is threaded to the central turbine shaft, and the reaming drill bit is threaded to the reaming drill bit connecting shaft; the turbine stator is mounted on the turbine sleeve with an interference fit; the turbine rotor and heightening ring are fitted onto the central turbine shaft and fixed to the central turbine shaft by a clamping nut threaded to the central turbine shaft; the input gear and output gear are respectively mounted on the central turbine shaft and the reaming drill bit connecting shaft by fastening nuts; the gear carrier is mounted on the central turbine shaft 4. The sliding bushing is nested on the gear carrier, and the intermediate gear is nested on the sliding bushing. The sliding bushing and the intermediate gear are axially fixed by a positioning nut. The central turbine shaft is supported for rotation by an upper bearing and an intermediate bearing. Drilling fluid flows out from the jet port of the central turbine shaft and enters the turbine assembly. The reaming bit connecting shaft is supported for rotation by a lower bearing. Drilling fluid flows out from the turbine assembly and enters the guide hole of the central turbine shaft and finally flows out from the reaming bit, without passing through the rotating gear system, thus avoiding severe gear wear. The input gear and the output gear are circumferentially fixed by a key.

[0022] Drilling fluid enters through the upper connector, passes through the central turbine shaft, and exits from its jet nozzle into the turbine assembly. After passing through multiple turbine stages, the turbine drill bit's rotational speed is reduced while its torque is increased, thus driving the lead drill bit for better drilling operations. The drilling fluid flows out from the last stage turbine rotor, re-enters the central turbine shaft, flows through the lead drill bit, and then exits. Simultaneously, as the central turbine shaft drives the lead drill bit to rotate and break rock, the planetary gear train causes the reamer's connecting shaft to rotate in the opposite direction to the central turbine shaft, thereby driving the reamer to perform reaming operations and creating a counter-rotation with the lead drill bit. The rotational speed ratio between the reamer and lead drill bit during counter-rotation can be controlled according to the gear ratio between the input, intermediate, and output gears.

[0023] The turbine rotor features a unique structure with circumferentially arranged tangential square holes in an axial flow configuration below the jet end face. A special pressure-type structure is also machined at the end face. When drilling fluid flows in axially, most of it passes through the pressure structure to form a high-speed jet; conversely, a small portion flows axially through the tangential square holes, creating a low-flow-rate jet. This rotor structure achieves both high-pressure jet generation, resulting in greater torque for the turbine, and reduced pressure drop while maintaining high torque output, thus improving turbine efficiency.

[0024] Driven by drilling fluid, the turbine rotor, through its special structure, forms a radial jet while simultaneously applying axial pressure, creating an axial flow. This causes the turbine to rotate with tangential force, transmitting the jet pressure to the next-stage turbine and driving the lead drill bit to rotate. The reaming drill bit is then driven to rotate via the directional gear set. Compared to traditional drilling tools, this effectively increases torque and allows for simultaneous reaming during drilling, saving costs.

[0025] Based on the above-described preferred embodiments of the present invention, and through the foregoing description, those skilled in the art can make various changes and modifications without departing from the inventive concept. The technical scope of this invention is not limited to the contents of the specification, but must be determined according to the scope of the claims.

Claims

1. A novel coaxial counter-rotating turbine drill bit with a jet motor, characterized in that: The novel coaxial counter-rotating turbine drill bit with jet motor includes an upper connector, turbine sleeve, upper bearing, central turbine shaft, clamping nut, turbine assembly, heightening ring, connecting sleeve, intermediate bearing, gear sleeve, planetary gear train, lower bearing, lower connector, reaming drill bit connecting shaft, reaming drill bit, and leading drill bit. The turbine assembly consists of a turbine stator and a turbine rotor. The turbine rotor has circumferentially distributed axial-flow tangential square holes below its jet end face. The end face of the main body of the axial-flow tangential square holes is provided with circumferentially distributed pressure fins. The planetary gear train includes an input gear, gear carrier, fastening nut, intermediate gear, sliding bushing, positioning nut, and output gear. The upper connector, turbine sleeve, connecting sleeve, gear sleeve, and lower connector are sequentially threaded together; the leading drill bit is threaded to the central turbine shaft, and the reaming drill bit is threaded to the reaming drill bit connecting shaft; the turbine stator is mounted on the turbine sleeve with an interference fit, and the turbine rotor and heightening ring are fitted on the central turbine shaft and fixed to the central turbine shaft by a clamping nut threaded to the central turbine shaft; the input gear and output gear are respectively mounted on the central turbine shaft and the reaming drill bit connecting shaft by fastening nuts, the gear carrier is mounted on the central turbine shaft, the sliding bushing is nested on the gear carrier, the intermediate gear is nested on the sliding bushing, and the sliding bushing and intermediate gear are axially fixed by a positioning nut.

2. The novel coaxial counter-rotating turbine drill bit with jet motor according to claim 1, characterized in that: The central turbine shaft is supported for rotation by an upper bearing and an intermediate bearing.

3. The novel coaxial counter-rotating turbine drill bit with jet motor according to claim 1, characterized in that: The reamer connecting shaft is supported for rotation by a lower bearing.

4. The novel coaxial counter-rotating turbine drill bit with jet motor according to claim 1, characterized in that: The input gear and the output gear are circumferentially fixed by a key.

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